Naturally, having a functional and more high-tech lethal torpedo affords the Navy an opportunity to hit enemies more effectively and at further standoff ranges and therefore better compete with more fully emerging undersea rivals such as Russia and China.

The Mk 48 heavyweight torpedo is used by all classes of U.S. Navy submarines as their anti-submarine warfare and anti-surface warfare weapon, including the Virginia class and the future Columbia class, Couch added.

A Mk 48 torpedo is 21 inches in diameter and weighs 3,520 pounds; it can destroy targets at ranges out to five miles and travels at speeds greater than 28 knots. The weapon can operate at depths greater than 1,200 feet and fires a 650-pound high-explosive warhead, available Navy and Lockheed data states.

Navy efforts to pursue new torpedo technologies are happening alongside a concurrent effort to upgrade the existing arsenal.

For several years now, the Navy has been strengthening its developmental emphasis upon the Mk 48 as a way to address its aging arsenal. The service restarted production of the Mk 48 torpedo mod 7 in 2016.

An earlier version, the Mk 48 Mod 6, has been operational since 1997 – and the more recent Mod 7 has been in service since 2006.

Lockheed Martin has been working on upgrades to the Mk 48 torpedo Mod 6 and Mod 7 – which consist of adjustments to the guidance control box, broadband sonar acoustic receiver and amplifier components.

“The latest version of the Mk 48 ADCAP (advanced capability) is the mod 7 Common Broadband Advanced Sonar System. The Mk 48 ADCAP mod 7 CBASS torpedo is the result of a Joint Development Program with the Royal Australian Navy and achieved initial operational capability in 2006,” Couch said.

With Common Broadband Advanced Sonar System, or CBASS – electronics to go into the nose of the weapon as part of the guidance section, Lockheed and Navy developers explained.

photo credit: seaforces.org

CBASS technology provides streamlined targeting, quieter propulsion technologies and an ability to operate with improved effectiveness in both shallow and deep water. Also, the Mod 7 decreases vulnerability to enemy countermeasures and allows the torpedo to transmit and receive over a wider frequency band, Lockheed and Navy developers say.

The new technology also involves adjustments to the electronic circuitry to allow the torpedo to better operate in its undersea environment.

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photo credit: seaforces.org

Modifications to the weapon have improved the acoustic receiver, replaced the guidance-and-control hardware with updated technology, increased memory, and improved processor throughput to handle the expanded software demands required to improve torpedo performance against evolving threats, according to Navy data on the weapon.

Improved propulsion, quieting technology, targeting systems and range enhancements naturally bring a substantial tactical advantage to Navy undersea combat operations. Attack submarines are often able to operate closer to enemy targets and coastline undetected, reaching areas typically inaccessible to deeper draft surface ships. Such an improvement would also, quite possibly, enable attack submarines to better support littoral surface platforms such as the flat-bottomed Littoral Combat Ships. Working in tandem with LCS anti-submarine and surface warfare systems, attack submarines with a more capable torpedo could better identify and attack enemy targets near coastal areas and shallow water enemy locations.

A Military Analysis Network report from the Federation of American Scientists further specifies that the torpedo uses a conventional, high-explosive warhead.

“The MK 48 is propelled by a piston engine with twin, contra-rotating propellers in a pump jet or shrouded configuration. The engine uses a liquid monopropellant fuel,” the FAS analysis states.

Submarine operators are able to initially guide the torpedo toward its target as it leaves the launch tube, using a thin wire designed to establish and electronic link between the submarine and torpedo, the information says.

“This helps the torpedo avoid decoys and jamming devices that might be deployed by the target. The wire is severed and the torpedo's high-powered active/passive sonar guides the torpedo during the final attack,” FAS writes.

Earlier this year, Lockheed Martin Sippican was awarded a new deal to work on guidance and control technology on front end of the torpedo, and SAIC was awarded the contract for the afterbody and propulsion section, Couch explained.

The Mk 48, which is a heavy weapon launched under the surface, is quite different than surface launched, lightweight Mk 54 torpedoes fired from helicopters, aircraft and surface ships.

The Navy’s Mk 48 torpedo is also in service with Australia, Canada, Brazil and The Netherlands.

Thanks for your comments and expertise - much appreciated. I am interested to take up your questions and see what more I can learn. Kris

CrowTRobot

Sep 12

They need to bring back the Sea Lance.

CConway

Sep 10

The US Navy needs an upgraded ASROC for ASW engagements at longer ranges. Building an upgraded Australian IKARA with Mk48 Torpedo capabilities is what it should look like. A longer lived booster, and a wing kit with guidance package and parachute let-down system should do the trick. Hopefully it will fit in a Mk41 VLS cell.

Duanen

Sep 8

A few comments:

The official reported range of the Mk48 is just 5 nm, but unofficial reports are widely published with range in excess of 20 nm, with range varying with cruise speed.

Also, the statement that our nuke submarines are capable of operating in shallower waters that deeper draft surface ships cannot navigate makes no sense at all. Subs require much MORE water depth than do surface ships do if they are to submerge, which submergance being the only way to maintain stealth. A US nuke sub requires at least 70 feet of water to submerge and still have only a couple of fert of water over the top of the sail and a couple of feet under the keel. Destroyers draw no more than about 28 feet give or take. Even a Nimitz class CVN draws no more than 41 feet.

The reality is that sub skippers hate to operate in shallow water. Our boats can and do operate in shallow waters, but shallow water increases the risk of detection (no thermal layers to hide under, and a sub can be detected visually in shallow water), and also reduces the ability of a sub to maneuver. Deep water is a submarine's ally.